diff --git a/src/common/PNGLibrary.cxx b/src/common/PNGLibrary.cxx
index 874bab478..1d9ae2c1b 100644
--- a/src/common/PNGLibrary.cxx
+++ b/src/common/PNGLibrary.cxx
@@ -304,7 +304,7 @@ void PNGLibrary::writeComments(png_structp png_ptr, png_infop info_ptr,
   if(numComments == 0)
     return;
 
-  png_text text_ptr[numComments];
+  unique_ptr<png_text[]> text_ptr = make_ptr<png_text[]>(numComments);
   for(uInt32 i = 0; i < numComments; ++i)
   {
     text_ptr[i].key = (char*) comments[i].first.c_str();
@@ -312,7 +312,7 @@ void PNGLibrary::writeComments(png_structp png_ptr, png_infop info_ptr,
     text_ptr[i].compression = PNG_TEXT_COMPRESSION_NONE;
     text_ptr[i].text_length = 0;
   }
-  png_set_text(png_ptr, info_ptr, text_ptr, numComments);
+  png_set_text(png_ptr, info_ptr, text_ptr.get(), numComments);
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -